Although it is the heart of winter, the Jewish calendar has now entered the month of Shvat, the month of Redemption. And this is the time we read the Book of Exodus, when G-d chooses the Jewish people to become His partners in saving the world.

Whereas the Book of Genesis was all about Creation and the forming of individuals – in Exodus the Jewish individuals which have become G-d's chosen family slowly develop into a nation, a nation which will be become pioneers in more ways than one.

As I write, my daughter has sent a photo by WhatsApp of being inoculated against Covid in Israel. And a photo of my son-in-law who has also now been inoculated by another of the four Israeli health insurance companies.

The importance of gleaning, which Judaism taught the world through the Book of Ruth, has also not been forgotten in Israel. Anyone who queues up at the inoculation centres can get a dose – because throwing life-saving medicines away is not only a sin in Judaism, it is also a crime. And in fact, nurses have run out into the streets in order to find passers-by to offer the jabs to at the end of the day.

What turned a rag-tag of miserable slaves, many the children and grandchildren of Holocaust survivors, into the nation that in the face of death always opted for life? To such an extent that they are being regarded today as the world's 'guinea-pigs'. What other group of people would be willing to test the efficacy of unknown vaccines, thereby doing the world an incredible favour – because who knows the repercussions of such advances in medicine?

However, in order to become the pioneering nation par excellence, the Jewish people had to undergo the miserable existence of slavery under Pharaoh – made all the worse because to start with Pharaoh 'knew' them. This means that their contribution to Egyptian society had been recognized by Pharaoh, and only then, when Pharaoh was doing well, did he get rid of the Jews as being surplus to requirements.

Pharaoh is the name not only for tyrants of empires with us no longer, but also for governments everywhere who simply get rid of their Jews when they are no longer required – the first being Edward I in England. In 1290, he made sure that the Jewish community were drowned in the Wash, after bleeding them dry with his wars in Scotland and Wales. And yet Edward is known as a good and very effective king.

To return to our initial prototype biblical Pharaoh, he no longer 'knows' the Jewish people, he pretends they don't exist. And to prove his contempt, he degrades them through humiliating and useless labours contrived to make no sense at all – exactly like Hitler who coined the phrase: 'Arbeit Macht Frei'.

Everyone knows that slavery never liberates. On the contrary, slavery leads to negative habits, and often to suicide. So, by bringing the new Jewish nation, known as 'the children of Israel', out of Egypt – G-d is testing their desire to be pioneers. And often there is backsliding and yearning for the comforts of past slavery. Even though they know that the Promised Land of Israel is in sight, the Jewish people never stop squabbling and complaining – and some even challenge Moses' leadership.

And during the time of these stories of the 10 Plagues and the journey through the Reed Sea, with Pharaoh changing his mind yet again and chasing after the slaves he has just 'let go'; their seemingly never-ending trek through the Wilderness and the epiphany at Sinai, site of the 613 commandments, when G-d appears to every man, woman and child, why do we suddenly celebrate in two weeks' time the important Festival of Tu B'Shvat, New Year for Trees?

Judaism is a religion of many parts: linear, cyclical, environmental, historical, spiritual and seasonal (just to name but a few). But with the Exodus stories starting in the heart of winter and morphing into the first signs of spring, what exactly do we celebrate at this time with Tu B'Shvat?

We celebrate the first appearance of the first almond, known in Hebrew as sh-k-d, an anagram for 'holiness' and also conveying the idea of watchfulness, with a connection to Jeremiah 1:11-12, where the tiny 'almond' becomes a 'watch-word'.

Here is Rashi's commentary on the 'almond' verse, which he wrote in northern France in around 1066, when fellow-Frenchmen were invading England and taking it over at the Battle of Hastings.

The almond is generally regarded as one of the most health-giving foods in existence – and one of its traits is that it is quite hard to crack, starts off with a bitter taste and then becomes sweeter as you get used to it.

This present Covid situation, which first started to be taken seriously in this country around Pesach (Passover) of last year, has everything to do with Exodus and almonds.

As early as Tu Bshvat last year, Israel started to make very difficult decisions in order to combat the oncoming plague. For instance, the spring Purim carnival, much loved by children, was cancelled. It is not yet known whether it will go ahead this year.

The month between Tu B'Shvat and Purim will be a seminal period when decisions will have to be made. Meanwhile all schools are still shut over there.

However, with people under 50 now being inoculated in Israel, it may be that the vast majority of adults will be inoculated by the end of February, just when Purim takes place, a month before Pesach (Passover).

So, during this festive time of plagues tempered with almonds and slavery tempered by liberation, who knows what the outcome will be. The only way forward is eternal vigilance – which has been the watchword of the Jewish people for 4,000 years.

Dr Irene Lancaster is a Jewish academic, author and translator who has established university courses on Jewish history, Jewish studies and the Hebrew Bible. She trained as a teacher in modern Languages and Religious Education.